Box



July 30,1946. B MELLER 2,404,916

BOX

Filed Oct. 24, 1944 2 sheets she et 2 INVENTOR. REGINALD 5. MELLER ATTORNEY Patented July 30, 1946 UNITED STATES PATENT OFFICE.

3 Claims.

This invention relates to an improvement upon the box disclosed in my application Serial No. 439,895, filed April 21, 1942, now Patent No. 2,366,- 419 of January 2, 1945. The box to which the invention of my patent and this application relate is one which can be completed from a blank without the use of adhesive to hold any of the corner components, the final box being one having substantial rigidity throughout and devoid of looseness or play at the corners.

In formin the box of my original invention, the blanks were cut with di es from a sheet of paper or other suitable material. For example, in one operation a substantially continuous sheet was fed to a rotary cutter cylinder carrying several dies spaced about its periphery. In this manner, the blanks were cut continuously as the sheet advanced through the machine. Successive blanks were not contiguous to one another and a small strip of waste material remained to be removed by hand from between the successive blanks. In accordance with the present invention, I provide a blank which can be formed from a substantially continuous strip and in which the successive blanks are contiguous to one another. This enab es any waste of material to be eliminated. In addition, the spoilage of blanks which frequently occurred during the waste stripping operation entirely obviated, as is the stripping operation itself. Further, the blank of this invention i so fashioned that the box can be assembled either by hand or by machine more rapidly, with greater ease. Finally, the assembled box possesses improved rigidity and stress resistance.

Other object and features of advantage will become further apparent upon a consideration of the following wherein I have further discussed the practic of the invention.

In the drawings accompanying and forming a part hereof, Figure 1 is a diagrammatic representation of the formation of the blanks in accordance with the present invention.

Figure 2 is an outside View in perspective of a corner of my improved box.

Figure 3 is an inside view in perspective of the same corner.

Figure 4 is an enlarged view of one corner of the box of the present invention illustrating certain variations which are permissible in the practice of the present invention.

Figure 5 is a side elevation showing the manufacture of a box including several of the corner constructions embodying the present invention.

Figure 6 is a view of a blank from which my improved box is formed.

Figure 7 is an enlarged view of one corner of the box of th present invention illustrating certain variations which are permissible in the practice of the present invention.

for a box blank indicated generally at 5 and of substantially rectangular form. The blank is scored as at lb, 2%) and 3G, to define and provide a bottom section i, side wall sections 9 and end wall sections H. Preferably score lines it) and 25?, extending longitudinally of the blank are offset slightly to facilitate conversion of the blank into an assembled box, as will presently appear. Extending from each end of an end wall section I i preferably integral therewith is a wing !3. If the box is made of rectangular form in general outline, free edge l5 of wing l3 and free edge ll of the adjacent side wall section 9 will be in alignment Each side wall section t, in proximity to each end thereof, is provided with a cut it into its free longitudinal edge. This cut i generally in a direction transverse to a circle 2i having its center at th nearest corner 23 of the bottom section 1. In the preferred embodiment, cut 19 will occupy a position in which the cut i between one in which the cut provide a continuation of a radius of the circle 23 and a second position in which the cut is parallel to cut 45 which separates the wing it from the adjacent side Wall 9. Thi phase of the invention will be discussed presently in detail in connection with Figure l. The cut is generally continued to the edge I? of the side wall by cut its, at a right angle to the side wall.

Each end wall wing E3 is provided with a cut 2?, transverse to the circle 2|, its direction being preferably at to the direction of the cut IS in the adjacent sidewall section 5; if cuts 2'! and ii! are extended, they will intersect at right angles to one another.

Cuts l9 and 21 terminate on the circle 2!. In accordance with the present invention, a third cut 29 is formed in the wings it along circle 2! this cut continuin to cut 48 to provide an extending tongue 45. Cut 29 is preferably made along the arc of circle 2| for if it is made within or without the arc to any material extent, the corner can be assembled but it is necessary to flex the several associated parts to permit the tab 55 to thread through out l5.

Referring now to Figure 1, the blanks are conveniently cut in a continuous manner with dies from a long sheet of suitable paper or board, the several blanks following each other successively, cuts 5| serving to sever and so separate one blank from a succeeding blank. This method of manufacture is inherent in the blank 0f the present invention. Its advantage will be further apparent upon reference to Figure l of my aforementioned patent and to the box blank there shown. This wa manufactured by cutting successive blank from a continuous sheet, successive blanks being separated from one another by a narrow separator strip of the sheet which was stripped off and wasted. When this was done, the blanks were placed in a pile and the unwanted material between tabs and 33 was removed by striking between tabs 25 and 33 with a hammer or other blunt instrument; unless this was carefully performed, tabs 25 and 33 were apt to be damaged and the blank or blanks ruined.

In forming a box from the blank of the present invention, the side wall and end wa11 sections 9 and II of the blank are creased along the score line I!) and 39 of the blank to form the side and end walls 9a and I l a, respectively, of the box; and either simultaneously with Or following such creasing, the end wall wings l3 are folded inwardly toward the side walls on crease lines 20. As the final step in the assembling of the box, the locking tab 46 of each wing i guided through a side wall cut l9 and forced forward until the edge of the side Wall tab 25 formed by such cut, snaps in behind the corresponding edge of the locking tab in a self-locking action and engages bottom 1 thereby efiectively and positively holding the end wall Ha in proper position with respect to the side walls 9a of the box.

Such self-locking action and positive support is attributable to the fact that the locking tab 25 of the side wall, during such assembling of the box, is stressed out of the plane of the side wall, and likewise the locking tab of the wing is stressed out of the plane of said wing, thereby establishing an existing tendency for these tabs to return to their original planes while tab 46 is held positively against bottom 1.

Arcuate cuts GI and 62 provided respectively at the ends of cuts 2'! and I9 enable the cuts to be interengaged readily and without tearing of the stuff of which the blank is made. The lengths of cuts 6| and 62 are varied to suit the thickness of the blank.

The 90 relationship between the cuts [9 and 21 associated at each corner forming section of the blank, bring the engaging edges of the looking taps 25 and 46 into line contact along the edges of cuts l9 and 21 for practically the entire length of these edges, as distinguished from a point contact existing in the prior art type of hook lock where there exists a definite crossing or intersection of engagin edges.

By spacing th side wall cut IS the same distance from the end of the side wall section 9, as the wing cut 29 is spaced from the edge of the end wall section II, interlocking of the tabs 25 and 46 will occur when an end wall section reaches its final position in abutment against the end of the side Wall section to form a box corner with tab 46 engaging bottom I, thereby preventing slack or looseness between the box components and creating a box corner of substantial rigidity against forces from either direction, the end wall being locked against movement either forward or rearward of it final position. In other words, the end walls and wings are swun only to their final position to obtain positive locking and support; it is not necessary to swing them beyond such position as in the hook type lock of the prior art.

The advantage of the present invention will be further apparent upon comparing the structure shown in Figure 3 of my prior patent and which is typical of my prior invention with the structure shown herein in Figure 3, for example. To resist a collapsing force applied against end I la in Figure 3 in my patent, one must depend on the engagement of cuts 2'! and I9 and some support from side So, because tab 33 terminates short of bottom 4 E. In the structure shown herein in Figure 3, tab 45 engages the bottom I and provides a positive support of definitely measurable and readily apparent value.

Referring to Figures 4 and 7, I have there indicated the variation which is possible in cuts [9, 21 and 29. I have previously indicated that cut l9 should be made in side wall 9 in a position intermediate those in which the cut lies along a radius of the circle 2| and is spaced 45 from out 40 which separates wing section I3 from side wall section 9. I have further stated that cut 21 should be made so that it terminates on circle 2| and so that if out 27 were projected it would be at to the projected line of cut is. I have found that the extreme positions of cuts 21 and i9 are as indicated by letters A and C in Figure 4, while the intermediate positions are typically and broadly represented by position B in Figure 4 wherein cuts 21 and I9 are at 90 to each other and where cut l9 lies between 10 and 20 removed from position A. I do not wish to indicate that positions A and C are inoperative. However, the best looking effect is obtained in one of the intermediate positions. In either position A or position C, the wing and side wall, when engaged, are interlocked only by a face-toface engagement parallel to the end wall. The locking secured with either position A or C is not nearly so effective as when the cuts are made in one of the intermediate positions. Positions D and E in Figure 7 represent the extreme preferred angular positions of cuts 21 and I9, Cut l9a is shown in Figure 4 as continuing cut I9 to the side .wall ed e I! at right angles to the edge. This is the preferred construction; however, as appears in Figure 7, cut 19 can run through to the edge at the same angle. The normal cut [9a facilitates threading of tab 45 into place.

A score line 35 across the tab 25 will provide a definite hinge line for the tab and thereby facilitate the operation of assembling the box from the blank, particularly for machine assembly or for the assembly of small boxes, by providing a groove at the junction with the wall cut IQ for the tab 46 to slide in, instead of the sharp narrow end of the cut. The score line further enhances the locking action in presenting an offset or ridge which effectively increases the abutting surface to the engaging tip of the tab.

Proper and effective functioning of the corner lock of my invention is, in large measure, based upon the use of sheet material which has the characteristics of stiffness and resiliency, for an efiicient locking will not be realized when employing sheet material, such as heavy paper or cardboard formed of soft pulp as is customarily employed in suit or hat boxes,

A sheet material which has proven very efficient as well as economical, is one developed particularly for this purpose, and comprises an intermediate layer of pulp, and an outer layer on one side of material known to the trade as glassine, and an outer layer on the other side of thin bond paper, both outer layers being adhesively secured to the intermediate layer by a suitable binder. The important feature in connection with this paper is the fact that a normal amount only of binder is preferably employed in adhesively securing the outer layer of bond paper to the intermediate layer, whereas the inner layer of glassine paper is adhesively secured by an amount of adhesive material sufficient to impregmate the intermediate layer for a substantial portion of its thickness. This adhesive, which may be that generally used in paper manufacture, has the property, upon drying, of rigidifying the impregnated portion of the intermediate layer, thereby increasing the stiffness and resiliency thereof on one side. These characteristics imparted to the material by the deep impregnation of one surface of the intermediate layer, further enable the formation of rather sharp corners between the components of the box when the blank is folded with the impregnated side of the intermediate layer facing inwardly.

My improved locking means permits of the design and construction of boxes of the boat type wherein the end walls Ila are of substant al y greater height than the side walls 9a. Boxes of this type lend themselves very nicely to the packaging and merchandising of commodities such as pastry, doughnuts and the like. By shortening ends II, the ends and sides can be made of the same height as appears in Figures 2 and 3 and the invention is not limited to boat type boxes.

In Figure 5 I have shown the improved corner and box construction of this invention as applied to a multiple unit of box in which several indi vidual locks are provided to provide a complete box. It will be obvious that the term end, bottom, and side may, in fact, refer to elements which, in the final structure are not in fact such. It will be obvious to those skilled in the art that these terms are broadly employed without the limitation normally imparted. In any case, the box and its contents may conveniently be wrapped with transparent material such as Cellophane, as the upper edges of the walls offer l adequate support for the wrapping, without nee essarily permitting the wrapping to snugly engage the contents of the boX. Waxed wrapping paper may also be used.

By reason of the rigid support offered to the end walls by my lock construction, the box, when wrapped with Cellophane or waxed paper, lends itself to heat sealing machine or hand, for the end walls and bottom can stand the sealing pressure without such flexing as would tend to weaken or break the seal upon removal of such pressure. This characteristic obtains. notwithstanding inward pressure distortion of the side walls due to any clamping means for holding the box during the sealing process.

While I have disclosed the preferred embodiment of my invention in detail, I do not wish to be limited in my protection to such details, as the embodiment disclosed by me is susceptible to change and modification, without departing from the principles and spirit of my invention. For example, the box may be constructed with end walls of the same or lesser height than the side walls by removing the corners of the side walls and placing the side wall cut in the horizontal edge thus formed. Another change contemplated, is to form the side wall cut is by providing a narrow notch in the edge of the wall. This would preferably be the practice where the box is to be formed of extra heavy material. Other changes will, no doubt, suggest themselves to those skilled in the art.

I claim:

1. A box having a self-locking corner comprising a bottom section, a side wall section and an end wall section, a wing extending from said end wall section adjacent said side wall section and separated by a cut from said side wall section, said side wall section having a cut in the longitudinal edge thereof in a direction transverse to a circle having its center at the corner of said bottom section to form a locking tab in ie plane of said side wall section, and said wing having a cut transverse to said circle and substantially normal to side wall section cut, and .cr cut extending from an extremity of said wing out to said separating wing cut substantially along an are through approximately the inner extremity of said side wall cut, to define with said out and separating cut, a locking tab in the plane of said wing adapted to be wedged through said side wall section cut during folding of said blank into box formation to automatically interlock with said side wall section tab edge to edge engagement therewith with said tab in engagement with said bottom to support positively said end wall section.

2. A box having a self-locking box corner comprising a bottom section, a side wall section and an end wall section, a wing extending from said end wall section adjacent said side wall section and separated by a cut from said side wall section, said side wall section having a cut in the longitudinal edge thereof transverse to a circle having center at the corner of said bottom section and at an angle between 10 and 20 to a line parallel to said separating out to form a locking tab in the plane of said side wall section, and said wing having a cut substantially normal to said side wall section cut, and another cut extending from an extremity f said wing cut to said separating out substantially along an arc of said circle passing through approximately the inner extremity of said side wall cut to define with said wing out, a locking tab in the plane of said wing adapted to be wedged through said side wall section cut during folding of said blank into box formation to automatically interlock with said side wall section tab in edge to edge engagement therewith and with said tab in engagement with said bottom to support positively said end wall section.

3. A box having a self-locking box corner coma bottom section, a side wall section and an end wall section, a wing extending from said end wall section adjacent said side wall section and separated by a cut from said side wall section. said side wall section having a cut in the longitudinal edge thereof in a direction transverse to a circle having its center at the corner of said bottom section to form a locking tab in the plane of said side wall section, and said wing having a cut transverse to said circle and substantially normal to said side wall section cut, said side wall out being spaced from the end of said side wall a distance substantially equal to the spacing of said wing cut from the end wall section, and another cut to said separating cut extending from an extremity of said wing cut substantially along an are through approximately the inner extremity of said side wall cut to define with said wing cut, a locking tab in the plane of said win adapted to be wedged through said side wall section cut during folding of said blank into box formation to automatically interlock with said side wall section tab in edge to edge engagement therewith and with said tab in engagement with said bottom to support positively said end Wall section.

REGINALD B. MEILER. 

